Base structure for miniature electron tubes



NOV. 18, 1947. s, os 2,431,198

BASE STRUCTURE FOR MINIATURE ELECTRON TUBES Filed Jan 4, 1945 IN VEN TOR.

5am POSQTZ Patented Nov. 18. 1947 UNITED STATES PATENT OFFICE BASE STRUCTURE FOR MINIATURE ELECTRON TUBES Sam Posen, Chicago, Ill., assignor to Beltone Hearing Aid 00., Chicago, 111., a corporation of Illinois 3 Claims.

This application is a division of my copending case Serial No. 526,877, filed March 17, 1944.

This invention relates to midget electron tubes and has for its main object to provide a midget electron tube which is particularly suited for the use in wearable hearing aids or similar small instruments to be enclosed in a flat casing.

It is a further object of the invention to pro- Vide a midget electron tube having a plug-in base which can be inserted into a socket whose axis may be arranged at any desired angle to the direction in which the axis of the tube is desired to be located.

Other objects of the invention will appear as the description proceeds, reference being had to the accompanying drawing which illustrates by way of example one embodiment of the invention and in which:

Fig. 1 is a perspective view of the tube;

Fig 2 is an elevational front view of a panel on which three electron tubes are mounted; and

Fig. 3 is a horizontal view to Fig. 2.

In Figs. 2 and 3, three midget electron tubes, generally indicated at I0, II and I2, are shown, whose bulbs l3, I4 and I5, respectively, are of flat shape. While in some cases bulbs of round cross section may be used it will in general be preferable to use the illustrated flat shape in order to require as little space as possible in the direction of the thickness of the instrument for which the tubes are used. This instrument may be, for instance, a hearing aid to be worn on the body of the user and the three tubes Ill, H, l2 shown in Fig. 2 may form part of the amplifier of such a wearable hearing aid. Each tube l0, ll, 12 is provided with a base l6, l1 and I8, respectively, arranged at a distance from the corresponding bulb. These bases IS, IT, l8 are ilat discsQtheir only purpose being to hold contact pins 19 in their proper relationship to each other. The bulb of each tube has no bodily contact with the base thereof and is connected to the base solely by the flexible leading-in wires 25 which are secured to the pins 9 of the base, and a substantial part of the length of these 1eading-in wires 28 extends freely between the bulb and the base. If desired, all or some of the wires 29 may be provided in a well known manner with a flexible insulating cover in the form of a coating or tubing (not shown) over those wire portions just mentioned extending freely between the bulb and the base. Sockets 2!, 2| mounted in a panel 24 are provided to receive the pins I 9 of the bases [6, ll, l8 of the tubes I0, ll, l2. With the bulb spaced from the base of the tubes in the manner just described the bulbs may be placed in any desired position with respect to the panel 24 and still be plugged into a socket permanently mounted in said panel. In the example shown, all three tubes I0, ll, l2 are arranged so that the axial plane of each tube comprising the larger dimension of the cross-section of the flat bulb extends in a plane parallel to the panel 24, that is, in a plane which is rectangular to the direction of the axis of each of the bases I6, ll, I8. While the bulbs are all shown to extend in the horizontal direction, each of these bulbs could extend under any desired angle to the horizontal direction or, as shown in Fig. 2 for the tube II, the bulb of any tube may be so arranged that its axis is some distance above or below the center of the corresponding base. Thereby the best possible use of the available space can be made in each particular case. It will further be seen that each tube H), II, or l2 may be easily exchanged without unsoldering the leading-in wires of the old tube and soldering on the leading-in wires of the new tube as has been necessary heretofore with midget tubes for wearable hearing aids and similar small instruments, these tubes having been used without a base.

The invention is not limited to tubes having any particular number of electrodes. The tubes may comprise no grid at all, or one or more grids and in the example shown they are assumed to be of the pentode type.

I desire it to be understood that while I have shown in the drawing a certain embodiment of the invention, this embodiment has been given by way of example only and that various changes and modifications may be made without departing from the spirit of the invention or the scope of the appended claims:

What I claim is:

1. A midget electron tube comprising a bulb, leading-in wires extending from the outside into said bulb, and a base to be plugged into a socket, said base being spaced from said bulb and connected with the latter solely by means of a flexible connection provided by a portion of said leading-in wires, that end portion of each of said leading-in wires which is next to said base plate being bent substantially perpendicularly to the remainder of the wire and extending at a substantially right angle to the longitudinal axis of said bulb. I

2. A midget electron tube comprising a bulb, leading-in wires extending from the outside into said bulb, and a base in the form of a plate carrying contact pins projecting perpendicularly therefrom to be plugged into a socket, said plate being spaced from said bulb and being connected with the latter solely by means of a flexible connection provided by a portion of said leading-in wires, that end portion of each of said leading-in wires which is next to said base plate being bent substantially perpendicularly to the remainder of the wire and extending at a substantially right angle to the longitudinal axis of said bulb and to the plane of said plate, into said contact pins.

3. A midget electron tube comprising a flat bulb, leading-in wires extending from the outside into said bulb, and a base in the form of a plate carrying contact pins projecting perpendicularly therefrom to be plugged into a socket, said plate being spaced from said bulb and being connected with the latter solely by means of a flexible connection provided by a portion of said leading-in wires, that end portion of each of said leading-in wires which is next to said base plate being bent substantially perpendicularly to the remainder of the wire, said bent-up end portions being substantially perpendicular to that axial plane of symmetry of the fiat bulb which comprises the long axis of the cross-sections of said flat bulb and to the plane of said plate and extending into said contact pins.

SAM POSEN.

REFERENCES CITED 

